ArgumentException: An item with the same key has already been added. (USDU-243)

[corybarr]

When attempting to reduce a model via the Simplygon Unity Plugin, the reduction fails with the following error:

ArgumentException: An item with the same key has already been added. Key: (10022.0, 10023.0, 10024.0)
System.Collections.Generic.Dictionary2[TKey,TValue].TryInsert (TKey key, TValue value, System.Collections.Generic.InsertionBehavior behavior) (at <695d1cc93cca45069c528c15c9fdd749>:0) System.Collections.Generic.Dictionary2[TKey,TValue].Add (TKey key, TValue value) (at <695d1cc93cca45069c528c15c9fdd749>:0)
Unity.Formats.USD.MeshExporter.ExportMesh (Unity.Formats.USD.ObjectContext objContext, Unity.Formats.USD.ExportContext exportContext, UnityEngine.Mesh mesh, UnityEngine.Material sharedMaterial, UnityEngine.Material[] sharedMaterials, System.Boolean exportMeshPose) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Geometry/MeshExporter.cs:394)
Unity.Formats.USD.MeshExporter.ExportMesh (Unity.Formats.USD.ObjectContext objContext, Unity.Formats.USD.ExportContext exportContext) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Geometry/MeshExporter.cs:224)
Unity.Formats.USD.SceneExporter.ExportImpl (UnityEngine.GameObject root, Unity.Formats.USD.ExportContext context) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Scene/SceneExporter.cs:269)
Rethrow as Exception: Error exporting: /X7100_UPITT_5TH_AVE_RENO_ARCH_CENTRAL_R20/X7100_UPITT_5TH_AVE_RENO_ARCH_CENTRAL_R20_rvt/Communication_Devices/TV_Samsung_Display/QM65R
UnityEngine.Debug:LogException(Exception)
Unity.Formats.USD.SceneExporter:ExportImpl(GameObject, ExportContext) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Scene/SceneExporter.cs:273)
Unity.Formats.USD.SceneExporter:Export(GameObject, ExportContext, Boolean) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Scene/SceneExporter.cs:176)
Unity.Formats.USD.SceneExporter:Export(GameObject, Scene, BasisTransformation, Boolean, Boolean, Boolean, Boolean) (at Library/PackageCache/com.unity.formats.usd@3.0.0-exp.1/Runtime/Scripts/IO/Scene/SceneExporter.cs:138)
Simplygon.Unity.EditorPlugin.SimplygonExporter:Export(ISimplygon, String, List`1)
Simplygon.Unity.EditorPlugin.SimplygonWindow:OnGUI()
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr, Boolean&)

[werez-sn]

+1

Same error but im not using Simplygon, i just have an FBX in Unity that produces this error.
It also DOES output a USDZ after the error, but material assignments are a bit messed up and no textures are brought across.

[vickycl]

Hi @werez-sn, thank you for reporting. Would you be able to share the FBX file so that we can reproduce this? It would also be useful to hear:

• your Unity version
• your package version
• whether the issue reproduces when exporting as USDC
  Thank you!

[werez-sn]

CORICart TV Only.zip

Hi @vickycl , sorry for the delay.

I have attached the problematic element of a larger mesh structure im not allowed to share.
Unity Version : 2020.3.8f1
Package Version : 3.0.0-exp.4
All export options produce the same error.

Notes from tests, if I remove the mesh renderer component from the export works correctly. Also even with the error, a file is produced but it is solid black. I tried just removing/changing the materials of the object but results were the same.